Distribution of lipoprotein species (LpA-I, LpA-I:A-II) in serum and HDL subfractions of untrained and trained normolipemic men

Cardiovascular disease risk factors in habitual exercisers, lean sedentary men and abdominally obese sedentary men

OBJECTIVE

To investigate whether the favourable cardiovascular disease (CVD) risk factor profile of habitual exercisers is attributable to exercise or leanness.

DESIGN

Cross-sectional study of 113 nonsmoking men aged 30-45 y. CVD risk factors were compared in exercisers (n=39) and sedentary men (n=74), and in subgroups of lean exercisers (n=37), lean sedentary men (n=46) and obese sedentary men (n=28). Waist girth was used to identify lean (<100 cm) and abdominally obese (> or =100 cm) subgroups.

MEASUREMENTS

Blood pressure, physical activity (7-day recall), physical fitness (maximum oxygen consumption) and fasted lipoproteins, apolipoprotein (apo) B, triglycerides, glucose and fibrinogen.

RESULTS

Exercisers were fitter and leaner than sedentary men and had a better CVD risk factor profile. Total cholesterol, LDL-cholesterol and apo B concentrations were lower in lean exercisers than in lean sedentary men, suggesting that exercise influences these risk factors. Indeed, time spent in vigorous activity was the only significant predictor of total cholesterol and LDL-cholesterol in multiple linear regression models. Exercise status had little influence on triglycerides and HDL-cholesterol (HDL-C), and unfavourable levels were only evident among obese sedentary men. Waist girth was the sole predictor of triglycerides and HDL-C, explaining 44 and 31% of the variance, respectively.

CONCLUSIONS

These findings suggest that the CVD risk factor profile of habitual exercisers is attributable to leanness and exercise. Leanness is associated with favourable levels of HDL-C and triglycerides, while exercise is associated with lower levels of total cholesterol, LDL-cholesterol and apo B.

The relationship between apolipoprotein AI-containing lipoprotein fractions and environmental factors: the prospective epidemiological study of myocardial infarction (PRIME study)

Apolipoprotein (apo) AI is distributed within high-density lipoproteins (HDL) between different types of particles, one containing both apoAI and apoAII (LpAI:AII), the other containing no apoAII (LpAI). We investigated the associations between LpAI and LpAI:AII with several factors such as body mass index (BMI), waist to hip ratio (WHR), alcohol intake, cigarette consumption and physical activity, in three French and one Northern Irish male populations included in a prospective study (PRIME study). LpAI and LpAI:AII were associated with variations in all environmental factors, except LpAI:AII, which was not associated with WHR. These relationships were unchanged after adjustment for other environmental factors, but slightly modified after adjustment for triglyceride levels. LpAI decreased when BMI, WHR and cigarette smoking increased, and increased with alcohol consumption and physical activity. LpAI:AII had a similar variation except for the absence of LpAI:AII modification associated with WHR variation. The associations between LpAI and BMI, alcohol consumption and cigarette smoking were largely dependent on HDL-cholesterol as indicated by the lack of any significance when the adjustment for HDL-cholesterol was made. Conversely, after adjustment for HDL-cholesterol, the significant association between LpAI:AII and BMI disappeared, while the associations between LpAI:AII and alcohol consumption, cigarette smoking and physical activity remained significant. These results suggest that the mechanisms of LpAI and LpAI:AII modulations differ according to each environmental factor, some dependent on the lipid content of lipoproteins and others not, but LpAI and LpAI:AII levels seem independent of triglyceride concentration.

Relation of percentage of body fat and maximal aerobic capacity to risk factors for atherosclerosis and diabetes in black and white seven- to eleven-year-old children

OBJECTIVE

To determine whether body fatness, aerobic capacity, and fat distribution are associated with levels of cardiovascular risk factors in children.

METHODS

Subjects (N = 57) were 7 to 11 years of age; their percentage of body fat ranged from 10% to 58%. The percentage of fat was measured with dual-energy x-ray absorptiometry, maximal aerobic capacity was measured on a treadmill, fat distribution was expressed as the waist/hip circumference ratio, and blood pressures were measured with an automated monitor. Measurements of several lipoproteins and apoproteins were combined into one atherogenic index.

RESULTS

The percentage of fat was related to the atherogenic index (p = 0.38; p > 0.01) and insulin level (p = 0.78; p > 0.001). Aerobic capacity was inversely related to the atherogenic index (p = -0.27; p > 0.05) and insulin level (p = -0.72; p > 0.001). The waist/hip ratio was not related to the risk factors, and blood pressures were not related to fatness or aerobic capacity. In multiple regression analyses, only fatness explained significant independent proportions of the variance in the atherogenic index and insulin level. After control for fatness, the black children had higher insulin levels (p > 0.05).

CONCLUSION

At early ages (7- to 11-year-old children), fatness was related to risk factors for cardiovascular disease and diabetes.